Fluid pressure device



March. 9, 1943.

c.-M. KENDRlcK ETAL 2,313,075

' FLUID PRESSURE DEVICE Filed March 25, 1939 2 Sheets-Sheet 1 Je f5 /9 50 4 f5 THSIR ATTORNEYS March 9, 1943.

C. M. KENDRICK EIAL FLUID PRESSURE DEVICE Filed March 23, 1939 2 Sheets-Sheet 2 05W/2; ,u "-iwd .Iran ,4. /fazzne BY THe/R ATTORNEYS Patented 9, 1943 j UNITED STATESl IPATENT ()FFICE i 2,313,975 i f 7- FLUID ransscaapavrcn Charles M. Kendrickl and Ivan A. Kaxine,..New

York, N. Y., assiznors to Manly Corporation,

New York, N. Y., a corporation of Delaware Application March 23, 1939, serial No. 263,649

' zi'claims. (o1. 10a-'120) This invention relates to vane type rotary iluid pressure devices, such, for example, as pumps or fluid motors, the volumetric capacity or output per revolution of which can be regulated or varied, and it relates, more particularly,

to improvements in that portion of the fluid presand the uid pressure device of the present invention will be described in connection with such use. It will be understood, however, that the invention is applicable to fluid pressure devices operating with elastic fluids.

Fluid pressure devices of the type under consideration include a rotor provided with vanes which are movable inwardly and outwardly, for example, in a general radial direction, and arranged to rotate within a chamberhaving side walls which closely fit the sides of the rotor and the side edges of the vanes. A trackway, which surrounds the outer ends of the vanes and controls their inward and outward movement, comprises one or more pairs of abutments and interconnecting track elements. One abutment of each pair is preferably arranged in fixed position adjacent the circumferential surface of the rotor and the other abutment of each pair is adapted to be adjusted inward and outward with respect to said circumferential rotor surface. With this preferred arrangement the work of the fluid pressure device is done while the vanes move across an arc on the working or movable abutment of each pair, termed the working or pumping arc, which, when the device is at other than zero stroke, is spaced from the circumferential surface of the rotor, forming a working or uid transfer chamber. The circulated iiuid is received on one circumferential end of this working chamber or pumping arc and discharged on the other.

The volumetric capacity or output per revolution of the uid pressure device is regulated or varied by adjusting the position of the working cr movable abutment of each pair with respect to the surface of the rotor. The interconnecting track element or elements serve to guide and conf vey the outer ends of the vanes from one abutment to another in all positions of the movable abutment, permitting adjustment of the movable abutment without changing the position of the other abutment of each pair.

The general object of the present invention is to provide an improved variable-capacity vane type fluid pressure device which operates smoothly Aand quietly, and is substantially free from vibration at hydraulic pressures up to and including 1,000 lbs. per sq. in. A further object is to provide a uid pressure device of this class having an improved trackway for the vanes in which all trackway members or elements are substantially rigid yet` which cooperate to form a substantially smooth and uninterrupted path of travel for the vanes at all outputs of the device. Other and more specic objects will appear from the description which follows. I

The invention will be understood from a consideration of the accompanying drawings which illustrate, by way of example, a preferred embodiment of the invention in a iluid pressure device having two working spaces employed as a so-called double-acting pump in which the vanes move inward and outward with respect to the rotor in a substantially radial direction. It will be understood, however, that the invention is also applicable to other iluid pressure devices which may be employed, for example, as iiuid motors and that the fluid pressure device can be made a single or single acting device having only one working chamber and also that more than the two working chambers may be employed, if desired.

In the drawings:

taken on the plane of line I I of Fig. 2.

Fig. 2 is a partial longitudinal sectional view I taken along the line 2 2 of Fig. l and of Fig. 3.

Fig. 3 is a similar but fragmentary view along the line 3 3 of Fig. 1, showing certain details of the pumps fluid circuit.

Fig. 4 is a perspective view of the elements comprising the improved vane track of the pump separated from but showing their relation to one another.

Fig. 5 is a transverse section taken along the line 5 5 of Figs. 1 and 2 and looking in the direction of the arrows, showing the casing end plate in position and also showing in dotted lines the fluid connections between the ports of this end plate and the inlet and outlet conduits in the pump casing, and

Fig. 6 is a transverse section taken on line 6 6 of Figs. 2 and 3, looking in a direction opposite to that of Fig. 5 as indicated by the arrows.

Referring now to the drawings, as shown-in Fig. 2, the pump includes a casing l0 and a head or cover Il which cooperate to form a cavity for the rotor I5 and associated parts. The rotor I5 is rotatably supported by its hubs I6 which extend into bushings l1 carried by the casing I9 and cover II respectively and said rotor is also provided with substantially radial vane slots in each of which is a vane I9 adapted to be moved radially inward and outward therein.

The pumps driving shaft 20 is revolubly supported upon a pair of bearing members 2l and 22 carried by the casing I and cover II respectively and shaft 20 passes through the central bore of the rotor I5 with which it has a slldable splined connection as clearly shown in Figs. 1, 2 and 4.

A substantially annular spacer block or ring 25 surrounds the rotor and vane assembly (Fig. 1) and separates a. pair of disk-shaped end plates, 26 and 21 which are provided with holes at their centers through which pass the hubs I6 of the rotor I5, as best shown in Fig. 2. The outer faces of the end plates 26 and 21 fit snugly against the adjacent wall surfaces of the casing I0 and cover II respectively and form substantially uid tight iits with the several ports and passages to be presently described. The inner or opposing faces of the end plates 26 and 21 form iiuid tight fits with the sides of the spacer ring 25 by which they are axially positioned with respect to the rotor I5 in such manner that the rotor is permitted to turn freely while its sides and the side edges of the vanes form substantially fluid tight running fits with the adjacent faces of said end plates 26 and 21.

The space within the chamber formed between the end plates 26 and 21 and which surrounds the rotor I5 is divided into a plurality of pumping sections, preferably two, each consisting of a working or pumping chamber iianked by :an inlet area and an outlet area. In the embodiment villustrated this space surrounding the rotor is divided into two pumping sections by a pair of diametrically positioned iixed abutments 30 (Fig. 1) which extend inward from the spacer ring 25 and are positioned above and below the rotor I5. Each fixed abutment is received within an appropriate recess formed in the spacer ring and is held in place by a screw 3l, as shown by dotted lines in Fig. 1, so that each fixed abutment forms a substantially fluid tight seal with the bottom` of its corresponding recess.

As best shown in the perspectivewview of Fig. 4. each fixed abutment 30 includes a central section 32 which is of the same width or thickness as that of the spacer ring 25 and thus forms a substantially fluid tight seal with the faces of the end plates 26 and 21. The interior surface ofeach iixed abutment 30 includes an arcuate surface 33, for convenience termed a sealing arc, pref- 40, acting in conjunction with the'rotor and vanes. Abutments 40 are shown in side elevation in Fig. l, and one is shown in perspective in Fig. 4. The pumping chambers are comprised by the spaces bounded by the rotor surface and the inner ends of abutments 40 and extend in a circumferential direction for an arcuate distance substantially equal to the distance between the two adjacent vanes which at any given instant are moving in contact with the arcs 4I (Fig, '4) on the inner ends of these movable abutments 40; the arcs 4I will be .referred to as the pumping arcs." The center line of each pumping arc 4| is preferably in line with the horizontal center line of its corresponding movable abutment 40, and the two pumping arcs and pumping chambers are thus diametrically opposite oneanother.

The size of the pumping chambers, and hence the volume of fluid delivered per-revolution of the rotor I5, is determined by the distance of the pumping arcs 4I from the circumferential surface of the rotor I5.

The movable abutments 40are arranged to be adjusted in a substantially radial direction to permit regulation or variation in the size of the pumping chambers and hence in the output of the pump. The movable abutments 40 are accordingly supported by and form substantially fluid tight fits with a pair of parallel slideways formed inthe spacer ring 25 as shown in Fig. l. The width of the movable abutments 40 is substantially the same as that of the spacer ring 25 and the arrangement is such that said movable abutments 40 likewise form substantially fluid tight sliding fits with the adjacent faces of the end plates 26 and 21. In this manner the movable abutments 40, in cooperation with the rotor I5 and the vanes I9, separate the inlet and outlet areas of each of the two pumping sections while permitting adjustment or variation in the size of the pumping chambers.

The movable abutments 40 are adapted to be moved inwardly and outwardly, in order to regu-y late the output of the pump, by means of a pair of adjusting rods 42 (Figs. 1 and 4).'the inner ends of which are received within suitable holes drilled in the movable abutments 40,.as indicated by dotted lines in Fig. 1, and the parts are fastened together by pins 43. The adjusting rods 42 extend through suitable holes in the spacer ring 25 and in the side covers I2 which close the horizontal adjusting rod bores formed in the casing I0. Movement or adjustment of the adjusting rods 42 and movable abutments 40 may be effected by any suitable means, not shown, which may be conveniently connected with the links 45 on the outer ends of the adjusting rods. Maximum outward movementl of the movable abutments 491s limited by the ends of the parallel slideways of the spacer ring by which said movable abutments are supported, and their maximum inward movement is limited by stop collars 46 formed on the adJusting rods 42.

yFluid is admittedv to the pumping chambers at the sides of the van'es as they approach each pumping chamber, and fluid is discharged from the pumping chambers in like manner as the vanes recede therefrom. This admission and discharge is accomplished through a pair of diametrically opposite arcuate inlet ports 50 and a similar pair of outlet ports 5I formed in the end plate 26 as shown in full lines in Fig. 5 and in dotted lines in Fig. 6; the ports 5I are also shown in the sectional view of Fig. 2. The end plate 21 is likewise provided with a pair of slmilar inlet po'rts 50 (Fig. 2) and a pair of outlet ports 5I which serve as balance ports to con- 'tain fluid under the same pressure as that in varies to prevent binding thereof. Fluid is also admitted and discharged, however, through theV ports in the end plate 2'I as fluid is free to pass to or from said ports through the clearance spaces intermediate the link members 1l, to be ywhich registers with the 'radially inner ends of the vane slots ofthe rotor- I5. AThe' vane slot ports 52 are connected with the discharge Iports I of their respective end plates by the grooves 53 formed on the outer faces of said end plates;

'thevane slot ports 52 and grooves 53 are shown in fullv line in Figs. 2 and 5 and are also shown by the dotted lines of Fig; 6. With thisl arv rangement pressure fluid from the outlet areas',

that is to say from the outlet ports 5I, is continuously supplied to theinner ends of all the vane slots where it actsupon the ends of the vanes I9 to urge them radially outward.

l'I'l'ie fluid `circuit also includes a branched inlet conduit 54 and an`annular outlet vconduit 55 as best shown in Figs. 2 and 5. Th'e inlet con- Yduit 54 is connected by sloping passages 58 with arcuate ports 5'I formed in the wall of the casing I0, as shown in Figs. 3, 5 and 6, the ports 51 registering with the inlet ports 5I of the end plate 26. The outlet channel 55 is similarly conv nected with the output ports 5I of the `end plate 26, this connection being through sloping passages 58 and arcuate ports 59 in the wall of the casing Ill as best shown in Fig. 2. Fluid is supplied to the pump from a suitable reservoir, not shown, through the inlet pipe 6I) and pressure fluid is discharged by the pump into the outlet pipe 6I which may be connected with any'suitable hydraulic device which is to be operated thereby. l

When the rotor I5 revolves in a counterclockwise direction as viewed in Fig, 1 fluid enters through the inlet ports 5D of the end plate 28 land passes into the inlet area of each of the two pumping sections of the pump. Pumping is accomplished by the vanes I9 as they move across the pumping arcs dI and the vanes I9 thus force fluid into the outlet areas of each of "the two pumping sections from which it passes out through'the outlet ports 5I of the end plate 26 and into the outlet coduit 55. As already stated the size of the pumping chambers and the volume of fluid delivered by the pump are determined by the distance of the pumping arcs dI from the rotor I5; as this distance may be varied in infinitely small increments from minimum to maximum, the size of the pumping chambers and the volume of uid delivered by the pump may likewise be varied from minimum to maximum.

The present invention is directed especially to the construction of the trackway by means of which the ends of the vanes are guided in their in-and-out movement as the rotor revolves. This trackway comprises the inner surfaces of the fixed abutments 30 and movable abutments d, and the inner surfaces of articulated interconnecting track elements which extend in a generally circumferential direction between these abutments to guide the vanes as they move from one abutment to another as the rotor revolves. In the present embodiment the interconnecting track elements, as shown in Figs. 1 and 4, take the form of rigid (that is to say, not readily bendable) links I0 the entire vane-contacting surfaces of which are of fixed curvature and 3l of the xed and movable abutments. 're. spectively,l which it connects. These reduced end portions. and 35 of the abutments extend into the slots or forks 35 and 31. respectively, of the links in such manner that the vanecontacting surfaces of each link overlap the vanefcontacting 'surfaces of the abutments, as will be understood from Figs. 1 and 4.

Each link 'I0 is pivotally positioned with respect to one of its abutments, preferably its fixed abutment 30 in this embodiment. As shown in Figs. 1 and 4 each link l0 is pivotally supported at a point near the outer end of an arm II which extends outward in a substantially radial direction at the end of link 'I0 adjacent xed abutment 30. In this manner the point of pivotal support is appreciably removed in a generally radial direction from the overlapping vanecontacting surfaces of the link I0 and its fixed abutment 30, for a purpose to be presently explained. The pivotal support of 'the link 'I0 comprises a pin 'I2 which in turn may be supported upon any suitable member such, for example, as the spacer ring 25, but is preferably carried by the corresponding reduced end portion 34 of fixed abutment 3l) in order that the two parts may be substantially self-aligning and thus facilitate and assure proper relationship between the portion of the overlapping vane track surface carried by` each of them.

It is essential that the vane-contacting surfaces of links 'I0 be maintained in vane-transferring relation with the vane-contacting surfaces of the abutments which they connect in order that the vanes may pass smoothly from one of these members to another. It is also necessary that such alignment be provided at al1 positions of adjustment of the movable abutments dll from zero to full stroke. 'I'he importance of this will be understood from the fact that the rotor I5 is frequently driven at a speed of 1200 R. P. M. or more and that each vane I9- passes to and from each of the track elements during each revolution of the rotor.

'Ihe point of transfer between each link 'I0 and its xed abutment 30 is preferably located upon the radius of curvature of the interior or vane-contacting surface of fixed abutment 30 which passes through the center of the corresponding-pivot l2, or conversely, each pivot 'I2 may be said to be preferably located upon the extensionof the radius of curvature passing through the corresponding point of transfer on the fixed abutment 30. I'he vane-contacting surface of' each link 'I0 on its end adjacent its corresponding fixed abutment 30 is formed with an arc 'I3 having the same center as that of the corresponding pivot pin 'I2 and having a radius equal to the distancer from the center of the pivot pin to the point of transfer on the vanc- .contacting surface of the fixed abutment 30.

This .arc 'I3 extends on to the link 1D for a distance suicient to engage or register with the point of transfer on the fixed abutment 30 throughout the range of swinging or rocking of said link 10 about the pivot 12 incident to adjustment of from its extreme outward to its extreme inward position. 'I'his arrangement provides smooth transfer of the vanes from the vane-contacting surface of the fixed abutment 30 tothe vane contacting surface of the link 10, and vice versa, in all positions-of adjustment of the vane track elements. and this smooth and vuninterrupted transfer is not affected by'movement of the links. The location of the pivot points 12 at points appreciably removed from the vane-contacting surfaces contributes to the smooth transfer thus obtained and permits swinging or rocking movement of thelinks relative to the fixed abutments without angularity between thevanecontacting surfaces of these members at the points of vane transfer which would produce an excessively abrupt' change in theV rate of radially inward and outward movement of the vanes. The portion of each arc 13 which is contacted by the ends of the vanes changes conformably with the amount of swinging of the links, so that the circumferential length of the vane trackway adjacent the transfer point on the fixed abutments is increased as the links swing outward, upon outward adjustment of the movable abutments,l and vice versa.

In this connection it may be stated that'in the particular embodiment illustrated thepoints of Itransfer on the fixed abutments 30 (Fig. 1 are preferably spaced, in a circumferential direction, a distance from the arcs 33 which is somewhat greater than that necessary to permit swinging of the links 10 into their extreme inward position toward the rotor I5. The vanecontacting surfaces 65 of reduced end portions 34 of the xed abutments 30 intermediate the arcs 33 and the transfer points are preferably given a curvature of slightly but gradually increasing radius`so that the transfer points are radially separated from the circumferential rotor surface for a distance slightly greater than that between the rotor surface and the arcs 33. The vane-contacting surface 66 on each link 10 extending from the arc 13 toward the corresponding movable abutment 40 may be given any suitable curvature and considerable latitude in contour is permissible, particularly when all of the vanes are continuously urged outward by action of pressure fluid from the discharge area upon the inner ends thereof as in the present embodiment. For example, this vane-contacting surface 66 may include an arc (not designated by a reference numeral) which is concentric with the rotor i when the link 10 is in its extreme inward position and it may be joined with the arc 13 in any suitable manner, as by a common tan- `erent therewith or by an intermediate portion the curvature of which gradually increases as it approaches the arc 13; this concentric arc does not extend, however, across the entire length of the links vane contacting surface but to an intermediate point which in the present instance is approximately midway between the ends of the link where it is smoothly joined with the contiguous portions of the links vane-contacting surface which will be presently described. This arrangement of transfer point and of curvature of the vane-contacting surfaces adjacent thereto permits use of a relatively small clearance between the surface of the rotor I5 and the arcs 33 without danger of any binding of the rotor by the links and provides satisfactory radially inward and outward movement of the vanes the corresponding movable abutment ythroughout the-range of swinging movement ofy the links. The'small amount of radial movement of the vane occurring adjacent the'transpump) is negligible and does not adversely affect the pumps operation.

It is also necessary, as previously stated, to

provide smooth transfer of the vanes as they pass from the vane-contacting surfaces of the links 10 onto the vane-contactingsurfaces of the movable abutments 40, and vice versa. Moreover this smooth and uninterrupted transfer must be provided in al1 positions of the movable abutment and the arrangements must alsobe such that relative motion is permitted between the links 10 and the movable abutments 40 in order that said movable abutments may be freely adjusted inward and outward to alterv the pumps output. In the preferred embodiment the adjacent end of each link 10 is adapted to have an extensible connection with its contiguous movable abutment 40. This extensible connection is` provided by means of a pin 14 (Fig. l) closely fitted in holes 15 (Fig. 4) in the ends of link 10 and slidably fitted into a slot 41 which is formed in the reduced end portion 35 of the movable abutment 40 that extends into fork 81 in the adjacent end of said link 10. In this manner the vane-contacting surfaces on the movable abutment 40 overlap those on the link 10 and relative sliding and rocking movements between the two parts are permitted simultaneously.

The links 10 swing outward, about the pivots 12, when the movable abutments 40 are moved in an outward direction and at the same time the pins 14 slide in the slots 41 in a direction away from the horizontal center line so that the length of the overlapping portions of the vanecontacting surfaces on the links and movable abutments is reduced and the circumferential length of the vane trackway is increased. The reverse is of course the case when the movable abutments 40 are moved in an inward direction. The slots 41 are so positioned and their configuration is such that a point on the portion of the vane-contacting surfaces on the fork 31 of the link 10 is maintained substantially even with the overlapping vane-contacting surface S1 on the end portion 35 of the corresponding movable I abutment 40; or in other words each slot 41 may be said to be positioned along the line generated by movement of the pin 14 when the vane-contacting surface of the link 10 is kept in proper relation to the vane-contacting surface of the movable abutment 40 and said movable abutment 40 is adjusted from its extreme outwa-rd to its extreme inward position. A line so generated has, theoretically, a. slight curvature but this curvature is so extremely small that in practice it often may be neglected and the slot i411 may be straight as in the present embodimen As shown in Figs. 1 and'2, the flat side surfaces of the spacer ring 25 are cut away to form arcuate recesses 24 extending intermediate the xed and movable abutments and positioned adjacent the inner circumference of spacer ring 25. The purposes of these recesses 24 is to provide clearance for the ends of the links 1D adjacent the movable abutments 40 as said movable abutments are adjusted toward their extreme outward positions. Only a relatively small part of each recess 24 is needed for this purpose but manufacportions 35 on each movable abutment have the same curvature as that of the pumping arc 4|. The vane contacting surfaces 68 on the adjacent'ends of the links 10 in this preferred embodiment have a contour approximating a segment of a parabola which smoothly joins the vane-contacting surface 61 of the movableabutment 40 when said abutment is in its half stroke position. This approximate parabolic contour 68 extends to about the middle of the link and to a point near the end of the previously described arc 66 which is formed on the end of the link adjacent the fixed abutment 30, the two curves being smoothly joined.

The above described arrangement provides smooth transfer of the vanes as they pass onto and away from the movable abutments 40, and the vane-contactin-g surfaces of the links merge so smoothly with the vane-contacting surfaces of the movable abutments that in practice a considerable part of their overlapping portions appears to be substantially coincident.

The links l are moved conformably with the extent of inward and outward adjustment of the movable abutments 40 and the relative positions of the links are accurately controlled throughout the entire range of adjustment. The links lil move relative to both the xed abutments 30 and the movable abutments l0 and have their movement coordinated with the movement of the movable abutments 40. The track surface has extensible connections at the ends of the In other links 'l0 with both their corresponding xed and movable abutments, whereby an increase or decrease in circumferential length of the vane trackway takes place at each end of the link incident to outward or inward adjustment of the movable abutments. 'Ihe relative amount of change in circumferential length of the vane trackway taking place at each end of the links is determined by its pivot 'l2 and may be distributed between the ends of each link in varying prothe Xed abutment 30. Substantially all of the change in circumferential length may be made to occur adjacent the xed abutment, however, with relatively little such change adjacent the movable abutment, by moving the pivot points outward in a substantially radial direction until they occupy positions in which a line drawn through the centers of the two pivots in each pumping section (which is a vertical line in the present embodiment) extends through the regions of Vane transfer on the corresponding movable abutment. The distribution of this change in trackway length between opposite ends ofV a link may therefore, as already stated, be altered to provide numerous ratios by change in location of the pivot. It is preferable, however, to remove the pivot point as far outward as possible from the point of transfer on the fixed abutment and to position said pivot uponV an extension of the radius of curvature passing through said transfer point, as this arrangement will provide smoothest vane transfer between the vane-contactingl surfaces of the link and the fixed abutment. Practical considerations such as size of the casing I0, the spacer ring 25, etc. usually impose certain limitations upon the location of the pivot points and the approximate locations as illustrated in connection with the present embodiment will be preferable for practical reasons in many instances. Pivot points located in the approximate relative positions shown inthe accompanying drawings produce somewhat greater change in circumferential track length at the ends of the linksadjacent the movable abutments than at the ends thereof adjacent the fixed abutments.

A Vane track embodying the construction above described provides smooth transfer at all points of connection between the several vane track elements and at all positions of adjustment of the movable abutments. This transfer of the vanes makes possible quiet and steady operation of the pump, and the terms smooth vane transferring relation, vane transferring relation" and other forms of these general expressions refer to transfer of the vanes with which pump operation of this character may be obtained. Numerous variations in this arrangement may be made, however, such, for example, as change in location of the pivot points or change in contours of the vane-contacting surfaces, etc. The arrangement described has, however, been found to function satisfactorily.

'I'he construction and arrangement of the vane track elements and associated mechanism are important features of this invention and have numerous advantages. For example, the vane track consists entirely of rigid elements, that is to say, no flexing or bending of any of them is required to provide smooth transition and it is accordingly possible to heat-treat all parts to have any desired degree of hardness. The track presents substantially no resistance to adjustment and the movable abutment may be moved inward and outward with very little eort. This is important particularly in instances where it is desired to use hydraulic adjusting mechanism which is actuated by pressure iiuid delivered by the pump itself as it permits such hydraulic adjustment at low pressures of the discharged fluid.

The present construction also makes it possible to provide pumps of small capacity having rotors of relatively smalldiameter as-the link construction allows free movement of the several coordinated track members throughout a wide range of sizes. possible to use a relatively wide rotor as the tracks of the present construction impose no limitation on rotor width. The manufacturing is facilitated by the fact that there are only three different elements in the track, that is to say, the xed abutments, the links and the movable abutments respectively, so that these parts may be made in quantities. A still further ad- Vantage is that the parts are readily interchangeable which also facilitates production.

The vane track elements are also easy to assemble. The links 'l0 are i'lrst mounted upon their pivots 'l2 on the xed abutments 30 and The present construction also makes itY -tne pme u ere then inserted into tnesiote n. of

the movable( abutments 40. The entire vane track `is then put into place inthe spacer ring and the fixed abutments are fastened in position by thescrews 3|. The pins-12 which form the pivots for the links require no 4fastening as f they are heldin position by the end plates 26 preferable to fasten thesepins in place in the` holes 'I5 as by riveting the ends of the pins or assembling the parts when the temperature 'of n the pins is appreciably belowv that of the links.

While the device has been described as a` pump it may also be employed for other purposes; for

example, it will also function as a fluid motor if supplied with pressure fluid for its operation 'but the cycle .of operation will of course be reversed. -When employed as a motor it is necessary to introduce means tending to hold the vanes i9 radially outward, particularly if the motor is to be operated at low rotative speeds.

It is to be understood that the foregoing is merely van exemplifying disclosure andthat 'changes may be made in the apparatus without departing from the invention which is the appended claims.

We claim: e 1. In a rotary fluid pressure device of variable deilned in capacity, a rotor, a plurality of vanes movable ,A

, oted nearer one of said track elements than the other and having an extensible connection with the other of said track elements, the entire vanecontacting surface of said link being of xed curvature.

- 2. In a rotary fluid pressure device of variable capacity, a rotor having a plurality of vanes movable inwardly and outwardly thereof, a Vtrackway'for the vanes comprising a stationary track element, a track element lmovable to vary simultaneously the capacity of the device and the length of the trackway, and a link member having at each end an extensible connection of its track surface with the track surface of one of the track elements, the entire track surface of said link member being of xed configuration, and

` pivot means for maintaining the track surface of one'end of the link member in vane-transferring relation with the track surface of the track element contiguous thereto. i

3. In a vane fluid pressure device of the class l described, a vane trackway comprising a fixed abutment, a movable abutment and an interconnecting track member having at each enda Joint with one of said abutments including overlapping track surfaces, pivot means for maintaining the track surface of one end of the interconnecting track member in smooth vanetransferring relation with the surface of one of the abutments at al1 positions of adjustment of the movable abutment, and sliding means for maintaining the track surface of the opposite end of said member in smooth vane-transferring relation with the surface of the other abutment.

neously the capacity of the device and the length of the trackway, and a link member whose entire vane-contacting inner surface is of nxed curvature interconnecting the stationary and movable track elements, said link member having the inner surface of one end pivotally maintained in even relation with the face of one of the-track elements, and at its opposite end having a slidable connection with the other lof the track elements, said slidable connection including sliding means for maintaining the inner surface of the link member even with the contiguous track element.

5. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of the rotor, and a trackway for th vanes comprising a stationary track element, a track element movable to vary simultaneously the capacity of the device and the length of the trackway, and a link member arranged to connect said track elements in all positions of said movable track element and having at each end an extensible connection of its track surface with the track surface of the adjacent track element.

6. In a rotary fluid pressure device of variable capacity, arotor, a plurality of vanes movable inwardly and outwardly of the rotor, a trackway for the vanes comprising a stationary track element, a track element movable to vary simultaneously the capacity of the device and the length of the trackway, and an interconnecting track member extending in a generally circumferential direction of the rotor and having at each end an extensible connection of the track surface'.

thereon with the track surface of one of the track elements. said extensible connections each including a track surface on4 the interconnecting member overlapping a track surface on the corresponding track element, the entire track surface of said interconnecting track member being of fixed contour, and means for maintaining the said overlapping track surfaces vin smooth vanetransferring relation with one another in all positions of adjustment of the movable track element.

. trackway for guiding the outer ends of the vanes in their in and out movement, means for ad Justing the movable abutment radially to vary simultaneously the capacity of the device and the 4. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of the rotor, a trackway for the vanes comprising a stationary track ele ment, a track element movable to vary simultacircumferential length of the trackway, said trackway comprising the faces of the abutments and an interconnecting track member, one of the abutments having an end portion provided with a track surface gradually receding from the rotor, the interconnecting track member having a sliding connection on at least one of its ends with the end portion of the abutment contiguous thereto, and pivot means directly connected with said interconnecting track member for controlling the interconnecting 'track member as the movable abutment is adjusted, said pivot means being disposed towards that end of the interconnecting track member which coacts with the abutment having an end portion provided with said gradually receding track surface.

a plurality of vanes movable inwardly and outwardly thereof, a casing therefor including a pair of stationary abutments coacting with opposite sides of the peripheral surface of the rotary as' sembly, a pair of movable abutments coacting with the opposite sides of the peripheral surface of that assembly intermediate thestationary 'abutments, linkmembers for guiding the outer ends of the vanes in their in and out movement as they rotate from one to another of the abutments, the faces of said abutments and of said link members comprising a trackway of variable circumferential length'for said vanes, and means for adjusting. the movable abutments radially to vary simultaneously the capacity of the device vand the circumferential length of the trackway,

each link member being pivoted at one of its ends adjacent an -abutment of one of said pairs and at its opposite end having an extensible connection with an abutment of the other of said pairs, the entire face of each link member having a fixed curvature.

9. In a rotary fiuid pressure device of variable capacity, a rotary assembly including a rotor and a plurality of vanes movable inwardly and outwardly thereof, a casing therefor including a pair of stationary abutments coacting with opposite sides of the peripheral surface of the rotary assembly, a pair of movable abutments coacting with opposite sides of the peripheral `surface of that assembly intermediate the stationary abutments, and linktrack members for guiding the outer ends of the vanes in their in and out movement as they rotatefrom one to another of the abutments, the vane-contacting surfaces .of said abutments and of said link track members forming a trackway of variable circumferential length for said vanes, means for adjusting the movable abutments radially to vary simultaneously the capacity of the pump device and the circumferential length of the trackway, the vane-contacting surface adjacent both ends of each link track member having extensible connections with the vane-contacting surfaces of the contiguous abutments, pivot means for 'maintaining the track surface of one end of each link member in vanetransferring relation with the surface of its contiguous abutment, and rockable means at the opposite end of each link'member for maintaining the track surface thereof in vane-transferring 'relationwith the surface of its contiguous abutment.

10. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and. outwardly in slots of the rotor, a trackway of variable circumferential length having a surface for guiding the ends of the vanes in .their in and out movement, means for simultane- 'decreasingly overlapsthe track surface on the contiguous element as the capacity of the device and circumferential length of the trackway are increased, and means for maintaining the overlapping track surfaces in smooth vane-transferring relation with one another to produce a smooth guiding of the vanes at any given capacity of the device.

11. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanesmovable inward and outward of said rotor in a substantially radial direction, a trackway of variable length for said vanes having two contiguous parts both of which are provided with track surfaces of fixed contour throughout which overlap one another near their adjacent ends in all positions of relative movement between said parts, one of said parts being mounted upon a pivot of fixed location and being movable in its entirety thereon in a path of varying angularity with respect to the other part as the length of the trackway is varied, and means for varying simultaneously the length of said trackway and the capacity of the device.

12. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly in slots of the rotor, a trackway of variable circumferential length having a surface for guiding the ends of the vanes in their in and out movement, means for simultaneously varying the circumferential length of the trackway and the capacity of the device, said trackway including two rigid track elements and a rigid interconnecting track member extending in a generally circumferential direction of the rotor and having at each end a track surface that overlaps in varying amounts the track surface on the contiguous elements as the circumferential length of the trackway is varied, sliding means for maintaining the track surface of one end of the interconnecting track member in smooth vane-transferring relation with the track surface of one of the track elements to produce a smooth guiding of the vanes at any given capacity of the device, and pivot means for maintaining the track surface of the opposite end of the interconnecting member insmooth vanetransferring relation with the track surface of the other track element, said pivot means being disposed radially outward from substantially the pointv of transfer of the vanes between the track surfaceof that track element and the interconnecting track member.

13. In a rotary fluid pressure device of variable capacity, a rotor having a plurality of vanes movable inward and outward thereof, and a trackway of variable circumferential length for said vanes, the length of said trackway increasing as the capacity of said device is increased, said trackway including a first abutment, a second abutment, at least one of said abutments being movable with respect to the other to simultaneously vary the capacity of the device and the circumferential length of said trackway, and an intermediate track member movable with respect to both of said abutments and adapted to con- Anect said abutments in all positions of relative movement therebetween, the entire vane-contacting surface of said intermediate track member having a xed curvature.

14. In a rotary fluid pressure device of variable capacity, a rotor having a plurality of vanes movable inward and outward thereof, a trackway of variable circumferential length for said vanes, said trackway including a first abutment, a rsecond abutment, at least one of said abutments being movable with respect to the other to simultaneously vary the capacity of the device and the circumferential length of said trackway, the length of said trackway increasing as the capacity of said device is increased, an intermediate track member movable with respect to both of said abutments and adapted to connect said abutments in all positions of relative movement therebetween, the track surface of said intermediate track member having a flxed contour throughout the circumferential length thereof, and means operative simultaneously with movement of one abutment with respect to the other to move said intermediate track member conformably with the relative movement between said abutments.

15. In a rotary fluid pressure device of variableIv capacity, a rotor having a plurality of vanes mov-'- able inward and outward thereof, a trackway of variable circumferential length for s'aid vanes,

said trackway consisting of a plurality of ele-- ments the entire track surfaces of all of which have fixed configurations and including a first abutment, a second abutment and an intermediate track member angularly movable with respect topboth of .said abutments, means for effecting relative motion between said abutments to alter the circumferential length of the trackway and the capacity of the device, and means functioning simultaneously therewith for altering the angular position of said intermediate track member connecting track member in vane transferring relation with the overlapping track surfaces on said abutments in all positions of said movable abutment.

17. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inward and outward of said rotor in a substantially radial direction, a trackway of variable length for said vanes having two contiguous parts both of which are provided with track surfaces of fixed contour throughout which overlap one another near their adjacent ends in all positions i of relative movement between said parts, and means for varying the length of said trackway as the capacity of the device is varied, the length of said trackway increasing as the capacity is increased, one of said two parts being movable in its entirety in a path of varying angularity with respect to the other part as the length of the trackway is varied.

18. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inward and outward of said rotor in a substantially radial direction, and a trackway for said vanes surrounding the rotor and vane assembly, said trackway consisting of elements in linked relation one to the other to form a substantially continuous van'e track surface for said vanes, the entire vane-contacting surface of each element being of xed configuration and at least one of said elements being movable to simultaneously alterV the capacity of the device and the circumferential length of said trackway, the length of said trackway increasing as the capacity of said device is increased.

19. In a rotary fluid pressure device of variable capacity, a rotor having a plurality of vanes movable inward and outward thereof in a substantially radial direction, a trackway of variable circumferential length for said vanes surrounding the rotor and vane assembly, said trackway comasisms prising a plurality of elements disposed in a generally circumferential arrangement .with respect to the rotor and vane assembly, the entire vanecontacting surface of each element having a fixed contour, eacn of said elements having on each of its ends a jointed connection with the element contiguous thereto, at least one of said jointed connections also' providing an extensible connection between the contiguous elements connected thereby, at least one of said elements having a pivotal mounting about which it is movable relative to an element contiguous thereto, and means for moving at least one of said elements to simultaneously vary the circumferential length of the trackway and the capacity of the device, the circumferential length of said trackway increasing as the capacity of the device is increased. L 20. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of the rotor in a substantially radial direction, a trackway for'the vanes comprising a stationary abutment, a movable abutment and track means disposed in articulated relation with respect to both of said abutments and connecting said abutments in' all i, positions of said movable abutment.

21. In a rotary fluid pressure device of variable capacity, a rotor having a plurality of vanes movable inwardly and outwardly thereof, a trackway for said vanes having a track surface of variable circumferential length, said trackway including a ilrst abutment, a second abutment and intermediate track means connecting said abutments in all positions of relative movement therebetween, means for moving one of said abutments to simultaneously alter the capacity of the device and the length of the track surface, and means operative simultaneously with movement of one abutment with respect to the other for moving said track means to increase the length of said track surface adjacent both abutments as the capacity of the device is increased and to decrease the length thereof adjacent both abutments as the capacity of the device is decreased.

22. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of the rotor and a trackway for said vanes having a track surface of variable circumferential length, said trackway comprising a stationary abutment, an abutment movable y to alter simultaneously the capacity of the device and the length of the circumferential track surface and means forconnecting the portions of the track surface on said abutments in all positions of said movable abutment including at least one track member disposed intermediate said abutments and arranged to simultaneously alter the circumferential length of the track surface adjacent both of its ends as the capacity of the device is varied.

23. In a multi-section rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of the rotor in a substantially radial direction, a trackway for said vanes, said trackway comprising opj positely positioned pairs of movable and fixed abutments and track means movable relative to and connecting said xed and movable abutments in all positions of said movable abutments, the track surface carried by said track means being of fixed contour, and means coordinating the movement of said track means with movement of able capacity, a rotor and vane assembly comprising a rotor having a plurality of vanes 'movable inward and outward thereof in a substantially radial direction, a trackway for said varies ment with respect to the rotor and vane assembly, each of said elements having a track surface of iixed contour and also having on each of its ends a connection with the element contiguous thereto including pivot mounting means, at least one of said elements being stationary, and means for moving at least one of said elements to vary the capacity of the device.

25. In a rotary uid pressure device of variable capacity, a rotor, a plurality of vanes movable inwardly and outwardly of the rotor ina substantially radial direction, a trackway for said vanes comprising a fixed abutment, a movable abutment and track means movable relative to and connecting said fixed and movable abutments in all positions of said movable abutment, the track surface carried by said means being of fixed contour, means for moving said movable abutment to vary the capacity of the device and means coordinating the movement of said track means with movement of said movable abutment.

26. In a rotary iluid pressure device oi' variable capacity, a rotor, a plurality of vanes movable inward and outward of the rotor in a substantially radial direction, a trackway for said vanes comprising a plurality of abutments including at least one abutment movable to vary simultaneously the capacity of the device and the circumferential length of said trackway, the length of said trackway increasing as the capacity of the device is increased, and track means connecting the abutments in all positions of said movable abutment, said track means comprising a plurality of track elements arranged for movement with respect to said movable abutment as the position of said movable abutment is altered, the entire track surface carried by each of said track elements being of fixed contour, means for moving said movable abutment and means operative simultaneously with movement of said movable abutment for moving said track elements correspondingly with the extent and direction of the movement of said movable abutment.

27. In a rotary fluid pressure device of variable capacity, a rotor, a plurality of vanes movable inward and outward of the rotor in a substantially radial direction, a trackway for said vanes, said trackway comprising at least two movable abutments and at least two stationary abutments and track elements movable relative to and connecting said movable and stationary abutments in all positions of said movable abutments, the track surface carried by each of said track elements being of ilxed contour, means for moving said movable abutments to alter the capacity of the device and means operative simultaneously with movement of said movable abutments for moving said. track elements to correspond to the positions to which said movable abutments are adjusted.

CHARLES M. KENDRICK. IVAN A. KAZINE.

cmIFIcArE oF CORRECTION. Patent no. 2,515,075. naz-.ch 9, 1915.

mams n. mDRIcx, man..

It is. hereby 'certified that errorlappears in the printed' specification of the above 'mnnbered patent requiring correction as follows: Page 5, first f column, line 50, for 'cutputf read -out1et; page 1|., second column, line 1|., for 'it' read.A is; line 69, for "prurposes'l read purpose; page 6, second colun, line 12, after 'with' insert that of; page 7, first co1- um, une ho, strike out "pmp" 5 une LLB,-after *rockable* insert -s11d1ng; and that the said Letters Patent snould be read with this correction therein that the same may confom to the record ofthe case in the Patent Office.

argued and sealed this 271:1; day of April, A. D. 19+5.

Henry Van Arsdale, 4(seal) Acting Commissioner of Patents'. 

